 /*******************************************************************************
  * Copyright (c) 2006, 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.ui.internal.navigator.resources.actions;

 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.ContributionItem;
 import org.eclipse.jface.action.IAction;
 import org.eclipse.jface.action.IMenuManager;
 import org.eclipse.jface.action.MenuManager;
 import org.eclipse.jface.action.Separator;
 import org.eclipse.jface.viewers.StructuredViewer;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.MenuItem;
 import org.eclipse.ui.IActionBars;
 import org.eclipse.ui.ISharedImages;
 import org.eclipse.ui.IWorkbenchActionConstants;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.actions.ActionGroup;
 import org.eclipse.ui.ide.IDE;
 import org.eclipse.ui.internal.navigator.resources.plugin.WorkbenchNavigatorMessages;
 import org.eclipse.ui.internal.navigator.resources.plugin.WorkbenchNavigatorPlugin;
 import org.eclipse.ui.internal.navigator.workingsets.WorkingSetsContentProvider;
 import org.eclipse.ui.navigator.IExtensionStateModel;

 /**
  * @since 3.2
  *
  */
 public class WorkingSetRootModeActionGroup extends ActionGroup {

     private IExtensionStateModel stateModel;
     private StructuredViewer structuredViewer;

     private boolean hasContributedToViewMenu = false;
     private IAction workingSetsAction = null;
     private IAction projectsAction = null;
     private IAction[] actions;
     private int currentSelection;
     private MenuItem[] items;

     private class TopLevelContentAction extends Action implements IAction {

         private final boolean groupWorkingSets;

         /**
          * Construct an Action that represents a toggle-able state between
          * Showing top level Working Sets and Projects.
          *
          * @param toGroupWorkingSets
          */
         public TopLevelContentAction(boolean toGroupWorkingSets) {
             super("", AS_RADIO_BUTTON); //$NON-NLS-1$
 groupWorkingSets = toGroupWorkingSets;
         }

         /*
          * @see org.eclipse.jface.action.IAction#run()
          */
         public void run() {
             if (stateModel
                     .getBooleanProperty(WorkingSetsContentProvider.SHOW_TOP_LEVEL_WORKING_SETS) != groupWorkingSets) {
                 stateModel.setBooleanProperty(
                         WorkingSetsContentProvider.SHOW_TOP_LEVEL_WORKING_SETS,
                         groupWorkingSets);

                 structuredViewer.getControl().setRedraw(false);
                 try {
                     structuredViewer.refresh();
                 } finally {
                     structuredViewer.getControl().setRedraw(true);
                 }
             }
         }
     }

     /**
      * Create an action group that will listen to the stateModel and update the
      * structuredViewer when necessary.
      *
      * @param structuredViewer
      * @param stateModel
      */
     public WorkingSetRootModeActionGroup(StructuredViewer aStructuredViewer,
             IExtensionStateModel aStateModel) {
         super();
         structuredViewer = aStructuredViewer;
         stateModel = aStateModel;
     }

     /*
      * (non-Javadoc)
      *
      * @see ActionGroup#fillActionBars(IActionBars)
      */
     public void fillActionBars(IActionBars actionBars) {
         synchronized (this) {
             if (!hasContributedToViewMenu) {
                 contributeToViewMenu(actionBars.getMenuManager());
                 hasContributedToViewMenu = true;
             }
         }
     }

     private void contributeToViewMenu(IMenuManager viewMenu) {

         IMenuManager topLevelSubMenu = new MenuManager(
                 WorkbenchNavigatorMessages.WorkingSetRootModeActionGroup_Top_Level_Element_);
         addActions(topLevelSubMenu);
         viewMenu.insertBefore(IWorkbenchActionConstants.MB_ADDITIONS,
                 topLevelSubMenu);
     }

     /**
      * Adds the actions to the given menu manager.
      */
     protected void addActions(IMenuManager viewMenu) {

         viewMenu.add(new Separator());
         items = new MenuItem[actions.length];

         for (int i = 0; i < actions.length; i++) {
             final int j = i;

             viewMenu.add(new ContributionItem() {

                 public void fill(Menu menu, int index) {

                     int style = SWT.CHECK;
                     if ((actions[j].getStyle() & IAction.AS_RADIO_BUTTON) != 0)
                         style = SWT.RADIO;

                     final MenuItem mi = new MenuItem(menu, style, index);
                     items[j] = mi;
                     mi.setText(actions[j].getText());
                     mi.setSelection(currentSelection == j);
                     mi.addSelectionListener(new SelectionAdapter() {

                         public void widgetSelected(SelectionEvent e) {
                             if (currentSelection == j) {
                                 items[currentSelection].setSelection(true);
                                 return;
                             }
                             actions[j].run();

                             // Update checked state
 items[currentSelection].setSelection(false);
                             currentSelection = j;
                             items[currentSelection].setSelection(true);
                         }

                     });

                 }

                 public boolean isDynamic() {
                     return false;
                 }
             });
         }
     }

     private IAction[] createActions() {

         ISharedImages sharedImages = PlatformUI.getWorkbench()
                 .getSharedImages();

         projectsAction = new TopLevelContentAction(false);
         projectsAction
                 .setText(WorkbenchNavigatorMessages.WorkingSetRootModeActionGroup_Project_);
         projectsAction.setImageDescriptor(sharedImages
                 .getImageDescriptor(IDE.SharedImages.IMG_OBJ_PROJECT));

         workingSetsAction = new TopLevelContentAction(true);
         workingSetsAction
                 .setText(WorkbenchNavigatorMessages.WorkingSetRootModeActionGroup_Working_Set_);
         workingSetsAction.setImageDescriptor(WorkbenchNavigatorPlugin
                 .getDefault().getImageRegistry().getDescriptor(
                         "full/obj16/workingsets.gif")); //$NON-NLS-1$

         return new IAction[] { projectsAction, workingSetsAction };
     }

     /**
      * Toggle whether top level working sets should be displayed as a group or
      * collapse to just show their contents.
      *
      * @param showTopLevelWorkingSets
      */
     public void setShowTopLevelWorkingSets(boolean showTopLevelWorkingSets) {
         if (actions == null) {
             actions = createActions();
             setActions(actions, showTopLevelWorkingSets ? 1 /*
                                                              * Show Top Level
                                                              * Working Sets
                                                              */
                     : 0);
         }
         workingSetsAction.setChecked(showTopLevelWorkingSets);
         projectsAction.setChecked(!showTopLevelWorkingSets);

         if (items != null) {
             for (int i = 0; i < items.length; i++) {
                 if(items[i] != null && actions[i] != null)
                     items[i].setSelection(actions[i].isChecked());
             }
         }
         if (stateModel != null) {
             stateModel.setBooleanProperty(
                     WorkingSetsContentProvider.SHOW_TOP_LEVEL_WORKING_SETS,
                     showTopLevelWorkingSets);
         }

     }

     /**
      * Configure the actions that are displayed in the menu by this ActionGroup.
      *
      * @param theActions
      * An array of possible actions.
      * @param selected
      * The index of the "enabled" action.
      */
     private void setActions(IAction[] theActions, int selected) {
         actions = theActions;
         currentSelection = selected;

     }

     public void setStateModel(IExtensionStateModel sStateModel) {
         stateModel = sStateModel;
     }
 }

